1. Field of the Invention
The present invention relates to an improved hidden type quick-release wheel hub assembly, and more particularly to a hidden type quick-release wheel hub assembly with a reinforcing arrangement to reinforce the structure.
2. Description of the Related Art
FIG. 7 of the drawings illustrates a typical quick-release wheel hub assembly that includes a hub 20 with an axial hole 21, each end of the hub 20 including a compartment 22 and a shoulder 23, two bearings 24 respectively received in the compartments 22 and respectively bearing against the shoulders 23, and a shaft 25 extended through the bearings 24 and the axial hole 21 of the hub 20. A nut 26 is threadedly engaged with an end of the shaft 25. FIG. 8 illustrates a sectional view of the quick-release wheel hub assembly. It is, however, found that the shaft 25, as having a smooth peripheral surface, may be moved longitudinally relative to the bearings 24 when it is subjected to a relatively larger force or it rotates at high speed. This results in an unstable structure. Namely, the hub 20 might be disengaged from the shaft 25 and thus endangers the cyclist. In addition, the shaft 25 is generally tubular for installation of the quick-release and thus adversely affects its strength. Namely, the shaft 25 tends to bend when subjected to a larger force. The present invention is intended to provide an improved quick-release wheel hub assembly to solve these problems.